Disclosure Of Fair Value Of Assets And Liabilities (Schedule Of Valuation Techniques And Significant Unobservable Assumptions) (Details) - Level 3 [Member] |
Jun. 30, 2021 |
|---|---|
| Measurement Assumptions, Discount Rates [Member] | |
| Fair Value Measurement Inputs and Valuation Techniques [Line Items] | |
| Office properties held for sale | 10 |
| Measurement Assumptions, Market Rental Rates Per Square Foot [Member] | |
| Fair Value Measurement Inputs and Valuation Techniques [Line Items] | |
| Office properties held for sale | 34.50 |
| Measurement Assumptions, Market Rates Per Square Foot [Member] | |
| Fair Value Measurement Inputs and Valuation Techniques [Line Items] | |
| Land properties held for sale | 12.00 |